1.- Use Hermes v4 or v4b payload to jailbreak
2.- Put your copy of MoH inside your external hard drive (If you have the same game I own it will have a *.pkg file bigger than 4 Gb just skip it)
3.- Inside Gaia Manager copy it over PC and copy it over the external drive and installed like any other *.pkg)
4.- Run the game with "Mem Patch" in Gaia.
5.- Enjoy